Construction of lead chambers for the manufacture of sulphuric acid



Oct. 5, 1937. R. MORITZ 2,094,956

CONSTRUCTION OF LEAD CHAMBERS FOR THE MANUFACTURE OF SULPHURIC ACID Filed Aug. 51, 1931 Gttornegs.

UNITED STATES PATENT OFFICE CONSTRUCTION 0F LEAD CHAMBERS FOR THE MANUFACTURE OF SULPHURIC ACH) Ren Moritz, Chatou, France Application August 31,

1931, Serial No. 560,525

In France September 3, 1930 3 Claims.

High chambers with bottom communications have given very interesting results in that the reactions in these chambers are considerably speeded up and that without artificial or costly means and without an excessive circulation of oxide of nitrogen, a considerable production is obtained per cubic metre of chamber space, and also per kilogram of lead employed in the construction.

Up to the present time it has only been possible to construct relatively small units with this arrangement. It had been thought possible to increase the dimension of. the pieces of apparatus by sending the gases issuing from the Glover tower into two or more series of parallel chambers, as shown in the drawing of French specification No. 571,206 of the 27th September 1925 in the names of R. Moritz and A. Sonneck. Practice has shown that it was impossible to obtain complete uniformity in this way and that sometimes one set worked faster and sometimes another, without any apparent reason. For this reason it is not possible to obtain the Whole useful effect from the chambers and the consumption of oxide of nitrogen increases when it is sought to produce as much per cubic meter of chamber space in such apparatus with a plurality of series of chambers as in apparatus having a single series.

The object ci. the present invention is to overcome these disadvantages.

Considerable study has shown that it is possible to construct very large chamber systems based on the principle of high chambers provided with bottom communications described hereinafter, in which all the chambers are in series and produce very considerable quantities of acid per cubic metre of chamber space on the order of 12 kilograms of acid calculated on monohydrated acid, while consuming only 0.8 to 0.9 kilogram of nitric acid of 36 B. per 100 kg. of monohydrated sulphuric acid, on condition that the ratio between the surface of the chamber walls in square metres and the Volume of the chambers in cubic metres remains in the neighbourhood of one to one and does not exceed in any case 1.2 to 1.

By working in this manner, it is possible to construct chambers from 15 to 25 metres high, 5, 10, 15, 20, 25 metres and more long, and 2.50 to 5 metres in width; this width may be as small as permissible by the use of atomizers or other means for introducing Water in a nely divided state.

Five to ten or more of these chambers are assembled together by means of short, very wide (Cl. .Z3-284) ducts connecting the lower part of one chamber with the lower part of the next. The gases from the reaction and the acids produced pass through these channels. The length of the channels is the same as that of the chambers, consequently 5, 10,15, 20 and 25 metres. This arrangement, hitherto unknown, gives novel results, but requires special precautions to be taken.

In the accompanying drawing:

Figure 1 represents a perspective View in part section of the apparatus showing the bottom communications for the passage of the gases interrupted; and

Figure 2 is a similar view of a modification with special ducts.

If we examine how the gases circulate in a high chamber with a bottom communication, we will see that the stream of gas under reaction which enters the chamber rises at I (Figures` 1 and 2), while exchanging and combining by turbulent movements its heat, its oxide of. nitrogen, its sulphur dioxide and its Water with the descending streams of gas at 2 and 3. Consequently, only the relatively more exhausted of the gases issue from the chamber after having given up their heat in contact with the walls, which has made them heavier. But the gases which descend so as to form the gas stream 2 are compelled to pass through the ascending gas stream I in vorder to pass through the bottom communication 8, which is difficult; these gases are thus compelled to pass round the gas stream I and pass at the side.

With the bottom communications of square or round chambers this does not present any difficulty, but with very large chambers the path to be followed by the gas stream 2 becomes too long and irregularities are produced. It is -thereiore necessary to employ means to avoid these irregularities.

1t is possible to do this by causing the stream 2 to penetrate the stream I by providing ducts which cause the gas stream 2 to pass through the gas stream I and rejoin the gas stream 3. The figures show the path of the gases when such ducts are provided in the chambers and the bottom communications are also interrupted. These ducts may be formed by small walls 6-6 made of acid proof bricks or other materials withstanding the local conditions. These walls are covered by slabs I and allow the gas stream 2 to pass through the gas stream I. If the spaces between the ducts are not too large, these ducts answer the purpose perfectly. The bottom communications may also be interrupted in width every four or ve meters by partitions, thus di- V50Y intense i productions 1 Y known` apparatusV which Vrequire a VveryV considviding the stream of Ygases into several streams end to end. Figure l'shows the pathof the gases in an arrangement in which the bottom communications are interrupted in width without pro- `5 vi'ding the above-mentioned'ducts. The ascending gas stream thenallows room, where Vthe interruptions' occur in the communications for, the descending gasY stream to pass, and theV apparatus Yworks extremelyruniforn'ily. The gas streams *Y do not become mixed, but remain in contact for effectingthe exchange of oxide of nitrogen, water, sulphur dioxide, etc. by diffusion, as Vexplained above. Y order of activity; the more exhausted gases leaveV l5 the chamber alone in orderrto pass belowzthe next bottom communication 8. Y

The very large surface of Contact between the gases and the acids from the bottom of theV lead l chamber passing through the bottomcornmuni-Y cations gives, by the simplest possible means, moments of 'reaction whichare still furtherv increased by Ythe fact that, in order to cool the Y 'gases from the chambers efectively, it is neces- Y Y sary to make the corridors 9 between the cham- Q bers much larger. 'Ihereis therefore ajvery large surface where the reactions are consider- Y V ably activated, so that with very little oxide of f Y nitrogen in circulation,V a much'Y greater num- Y ber ofreactions is obtained 'than in theY chambers of usual construction. Moreover, the.

whole ofthe production of acid is made Vto circulate towards the head chambenfrom which the whole of the production is drawn-oir. Consequently, the oxideof nitrogen is strongly absorbed by the tail acids, in the presence of the gases poor inV sulphur dioxide but rich in oxide of nitrogen. These very nitrous acids are completely de-nitried atlow temperature in the bottom head communications where they are in con-v Vtact with the gases rich in sulphur dioxide which Y Vhave stillundergonelittle reaction. .As a result, Y the: oxide of nitrogen is returned strongly into 'Y circulation in the interior of Vthe chambers `throughthe medium of the acid from the bottom ofjthelead chambers.

Although the work is'r'carried out at aerelatively low ktemperature vandrwith little oxide of nitrogen'in circulation, anY intensity of productionY isobtained which is greater than the most Y obtained with hitherto erable circulation;V of, Yoxide ofV nitrogen. 'The e the reaction at low temperature does not produce a' decompositon of oxide of nitrogen, thatV is to s ayoxides of nitrogen having variable compo- Grsitions kfromfNzOa vto NO2 which. arereduced to N20 and VN'when'the de-nitrifi'cation takesrplace Y at hightemperature in the Glover tower'or in Y The gases become classified by*v the ordinary so-called intensive working chamy bers. Y Y

An abbreviated description of the operation of this apparatus is Vhere given. Y Y

Referring to Figure 1, this shows a series of two or more intercommunicating reaction chambers eachV with a pluralitybf flat,'wide Yducts ilY Yparallel to the length direction of the chambers. VThese-chambersy are of considerable height and length but of narrow width and their bottoms are 'covered with-a thin layer of acid. The leading-V -in ducts are partly lled with the acids so that the reactiongases can pass over theminto the reaction chambers and over the layer Vof acid therein thus becoming heated, and travel in anf upward stream VI within the Vchamber and heat its walls. Thisv upward gas stream thus becomes heavier when Yreaching the top of the chamber Y Y' and then reverses its motion forming a downward stream, 2 and 3. The stream I exchanges and combines itsV heat and contentV of oxide of YVnitrogen, sulfur dioxide and water with the downwardy stream of heavy reactionV gases as YatY 2 and f 3, said two streams thus running in counter current. Y y

l 'I'hefrst and second as well as the second and third chambersrare connected by similar at, tu-

bula'r ducts 8, so that' the descending cooledV and exhausted gas streams 2, 3 fromthe first chamber pass through Vthe* ducts 8 into the Vsecond chamber and similarly from the second chamber to the third and so on.

VAs'the 'ascending gas stream I'may interfere with the easy passage along the bottom of the chamber of a descending gasrstream 2 near the inletduct 8, additional conduits 1 may' be provided` asin Fig. 2, to lead the gas stream without interferencerand Ymore directlyV to theY exit l opening and through ducts into the second chamy Y Y ber. Since .enough space is provided, above the level of the acid layer, to permit the reaction gas Y gas. y v

What Iclaimris: Y Q e 1. Lead chambers forrproduc'ing sulphuic acid,

Y to sweep'over it, no bubbles are Vformed by the Y45 said chambers being very high,V very long andr ofV small width, slot-like conduits interconnectingY`V the lower; parts of thefsaidfchambers,;said conduits extendingfhorizontally over the whole Y.

length of 'the'chambera thus permittingreaction gases to vpass through theconduits just above the acids, the ratioof the area of the chamber walls in cubic meters being aboutV Y1 to 1 and not ,ex-f u ceeding 1.2 to 1.'

- Lead chambers as claimed in clair-nfl inY which ducts' are provided between the conduit sections within vthe chambers and in the spaces between said conduits, said'ducts lbeing partlyV open onthetop. Y

Y, Y3. Lead chambers asgclaimed inlclai'm 1, in Y ,which ducts are provided; betweenV` the conduitl sections within thechambers and Vin the spaces Vbetween saidrconduits,V said ducts being partly open' onthe topsaid ducts being formed by two' vertical walls and a: superposed horizontal wall.

I l RENy MORITZ;

in squaremeters to theyolume ofthe'chamber 

